Tension control device



v July 2s, 1953 L. J. LINDSAY TENSION CONTROL DEVICE Filed June 1:5, 1951 jg INVENTOR ATTORNEYS Patented July 28, 1953 TENSION CONTROL DEVICE Luther Jackson Lindsay, Knoxville, Tenn., assignor of one-half to Hugh T. Overton, Knoxville, Tenn.

Application June 13, 1951, Serial No. 231,356

Claims.

This invention relates to improvements in tension control devices of the character used particularly for the automatic control of tension of thread or yarn in textile machines, particularly knitting machines. n V Various forms of tension control devices have been proposed heretofore, most of which have been unsatisfactory for one reason or another, but generally because of the complex structures involved, or the lack of adequate maintenance of uniform tension on the thread or yarn.

The object of this invention is to overcome the objections to prior tension devices and to improve the construction thereof so as to efect a uniform tension automatically for all diierent threadsor yarns without variations in adjustment ofthe device.

This object may be accomplished according to one embodiment of the invention by providing tension means to act on the thread or yarn under resilient tension, and additional means controlled by the thread or yarn and acted on by separate resilient means to vary the effect of the rst mentioned resilient means on the tension applying means. Tension discs may be used to apply tension directly to the thread or yarn, and acted on by a spring to vary the tension thereof. A member, preferably a lever, is mounted so as to be acted on by the thread after passing through the tension discs, and has means connected therewith to vary the effectiveness of the spring on the discs. It is preferred that a second spring be used, which also acts on the lever in opposition to the first mentioned spring thereon. This structure holds the same tension for all different yarns, applying a uniform tension or drag thereto which opens or closes automatically to accomplish this result.

This embodiment of the invention is illustrated in the accompanying drawings in which:

Fig. l is a side elevation of the tension control device;

Fig. 2 is a top plan View thereof partly in section on the line 2--2 in Fig. 1; and

Fig. 3 is a vertical sectional view therethrough with parts in elevation taken on the line 3--3 in Fig. 1.

The invention is shown in an embodiment that may be used for controlling the tension on thread of varying diameters between the cone or bobbin and a textile machine to which it is fed, such as a knitting machine. One embodiment is shown including a supporting frame generally designated at I, which is U-shaped, with upstanding opposite sides 2 and 3, respectively. The frame I may be mounted in suitable relation to the knitting machine for feeding the thread thereto, substantially as illustrated in Fig. 1. The thread is designated generally at T and is normally supplied by a cone or bobbin, generally designated at C. Guide eyes 4 and 5 are provided in the sides 2 and 3 of the frame through which the thread T extends and is drawn in passing from the cone C to the knitting machine.

Supported on the frame I in upstanding relation between the side arms 2 and 3 of the frame is a guide spindle 6, which is preferably secured .witln the frame I as by a screw or other fastening slidably mounted loosely on the spindle 6 is a pair of opposed tension discs 8, which may be formed of dished shape in cross section, or of other suitable form, as desired, for applying tension to the thread T that is drawn therebetween around the spindle and yieldably maintain tension on the thread. The discs 8 are retained on the spindle 6 by -a collar 9, secured rigidly in place on the spindle by means of a set screw I0. A helical spring II acts against the uppermost one of the tension discs 8, yieldably maintaining the pressure discs in contact with each other and with the collar 9.

The helical spring I I is sleeved over the spindle 6, bearing at its lower end on the pair of discs 8. A collar I2 is slidably mounted loosely on the spindle 6 and is seated upon the upper end of the helical spring II, bearing thereon for varying the tension of the spring, as desired. A second helical spring I3 is sleeved loosely upon the spindle 6, and is interposed between the collar I2 and a collar I4, secured rigidly to the spindle 6 in an adjusted position with respect thereto, as by means of a set screw I5. The collar I4 may be moved lengthwiseof the spindle 6 to vary the tension of the spring I 3, according to the amount of drag desired on the yarn, but ordinarily no further adjusting will be required for different yarns or threads being used.

The collar I2 is provided with aligned pins I6 on opposite sides thereof, as shown in Fig. 3. These pins I 5 are engaged by bifurcated end portions II, formed on one end of a lever I8. The lever I8 is pivotally mounted at I9 intermediate its length on the upstanding side arm 3 of the frame I.

The outer end portion of the lever I8 is oiset at 28 and is provided with a guide eye 2| xed therein, as shown in Figs. l and 2, for guiding the yarn therethrough, whereby the thread or yarn T acts on the outer end portion of the lever I8, to vary the position of the lever and thereby vary the tension according to the drag that develops in the thread.

In the operation of the control device it will be apparent that the thread or yarn T is drawn from the cone or bobbin C and passes through the stationary eyes 4 and 5, between the tension discs '8 and through the eye 2l of the lever I8, thence to the knitting or other textile machine to which the control device may be applied. So long as the yarn and the drag remain uniform, the lever I8 will remain in the same position,

thereby allowing the spring II to apply a uniform pressure on the tension discs 8 and the yarn that passes therebetween. If more drag develops due to a variation in the yarny or for any other reason, a pressure will be applied, tending to pull downward on the outer end portion of the lever I8. This in turn will act through the bifurcated end portions. I' at the inner end of the lever to lift the collar I2 and relieve the pressure on the spring II, thereby providing less pressure by this spring on the discs The amount of pressure applied by the collar I2 on the spring II may be varied also by the tension of the spring I3, which latter is set for the desired tension by adjusting the collar I4 acting thereon. The collar It then may be se? cured in place on the spindle 6 by the set screw I5, according to the amount of drag required, after which no further adjustment of this collar I i will be required for a normal use of the ten- Asion device.

This device will hold the same tension for all different yarns, providing a uniform tension which will open automatically when the drag develops thereon, or the tension will 'ce increased ii the yarn gets too light. Thus a very sensitive unit is provided to accomplish the desired results of maintairng uniform tension under all conditions, At the same time a very simple mechanism is all that is required to accomplish this result, one easily maintained and installed at low costi.

While the invention has been illustrated and described in one embodiment, it is recognized that variations and changes may be made therein Without departing from the invention as set forth in the claims.

I claim:

1. A tension control device for thread comprising a substantially U-shaped support having a pair of spaced arms, each arm of said support having a thread guide eye therein, a spindle mounted on the base o1" said support, a pair of opposed tension discs mounted on the spindle, means for limiting the movement of the discs in one direction, a spring bearing against the opposite side of the pair of discs in opposition to said limiting means, a collar slidably mounted on the spindle and bearing on the spring, pins projecting in opposite directions from the collar, a lever pivotally mounted on one of said arms and having a bifurcated end engaging the pins to vary the tension o the spring, and a thread guide eye connected with the lever in position to receive the thread after passing through the thread guide eyes and the tension discs to vary the tension applied to the thread.

2. A tension control device for thread comprising an arm having a thread guide eye therein, a spindle mounted on the arm, a pair or" opposed tension discs mounted on the spindle, means on the spindle for limiting the movement of the discs in one direction, a spring bearing against the opposite side of the pair of discs in opposition to said limiting means, a collar slidably mounted on the spindle and bearing on the spring, pins projecting in opposite directions from the collar, a lever pivotally mounted on the arm and having a bifurcated end engaging the pins to vary the tension of the spring, and a thread guide eye connected With the lever in position to receive the thread after passing through the tension discs to vary the tension applied to the thread, a second spring sleeved over the spindle and bearing on the collar, and a sec- Aio 4 ond collar mounted on the spindle and secured in an adjusted position with respect thereto for confining the second-mentioned spring.

3. A tension control device for thread comprising an arm, a spindle mounted on the arm, a pair of opposed tension discs mounted on the spindle, means for limiting the movement of the discs in one direction, resilient means bearing against the opposite side of the pair of discs in opposition to said limiting means, a collar slidably mounted on the spindle and bearing on said resilient means, a lever pivotally mounted on the arm, means pivotally connecting one end of said lever with said collar to vary the tension of the resilient means, and a thread guide eye connected with the lever in position to receive the thread after passing through the tension disc to vary the tension applied to the thread, a second resilient means mounted on said spindle and bearing on said collar, and a second collar mounted on said spindle and secured in position with respect thereto for conning said second mentioned resilient means.`

4. A tension control device for thread compris-.- ing a frame, an elongated member mounted on said frame, a pair of opposed tension members mounted on said elongated member, means for limiting the movement of said tension members in one direction, means bearing against the opposite side of said tension members in opposition to said limiting means, means slidably mounted on said elongated member and bearing against said second means, means pivotally mounted on said frame and connected with slidable means whereby actuation of said pivoted means moves said slidable means relative to said elongated member to vary the tension of said rst means on said tension members, means on said pivoted means to receive the thread therethrough after passing through said tension members to vary the tension applied to the thread, means on said elongated member bearing on said yslidable means, and means mounted on said elongated member for confining said last named means thereon.

5. A tension control device for thread comprising a frame, an elongated member mounted on said frame, a pair of opposed tension members mounted o n said elongated member, means on the elongated member for limiting the movement of said tension members in one direction, means bearing against the opposite side of said tension members in opposition to said limiting means, means slidably mounted on said elongated member and bearing against s aid second means, means pivotally mounted on said frame and connected with slidable means whereby actuation of said pivoted means moves said slidable means relative to ,said elongated member to vary the tension of said rst means on said tension members, means on said pivoted means to receive the thread therethrough after passing through said tension members to vary the tension applied to the thread, means on said elongated member bearing on said slidable means, and means adjustably mounted on said elongated member for coniining said last named means thereon.

LUTHER JACKSON LINDSAY.

References Cited in the file 0f this patent UNITED STATES PATENTS Number 

